As illustrated in FIGS. 1–4, a conventional method of mounting a removable restoration tooth “T” involves a first step in which an abutment 11 is formed on a tooth 10 to be restored. Thereafter, a matrix of the abutment 11 is made. On the basis of the matrix of the abutment 11, a metal inner crown 20 of a hollow construction is made. A matrix of the inner crown 20 is made for preparation of an outer crown 30. The inner crown 20 is fitted fixedly over the abutment 11 such that an inner wall 21 of the inner crown 20 is joined with the abutment 11 in conjunction with a cement “C”. Finally, the outer crown 30 of the restoration tooth “T” is removable fitted over an outer wall 22 of the inner crown 20. It must be noted here that the association of the outer wall 22 of the inner crown 20 and the inner wall 31 of the outer crown 30 of the restoration tooth “T” takes the form of interference fit.
The efficiency of the conventional method described above is dependent on the quality of dental works done by a dentist and a dental technician. For example, the formation of the abutment 11 and the making of the matrix of the abutment 11 are done by the dentist. The inner crown 20 is made by the dental technician on the basis of the matrix of the abutment 11. The outer crown 30 of the restoration tooth “T” is also made by the dental technician. It is therefore readily apparent that a work done by the dentist is a complement to the dental technician and vice versa. In addition, the making of the inner crown 20 is a time-consuming chore on the part of the dental technician in view of the fact that the inclination of the outer wall 22 of the inner crown 20 is crucial to a successful interference fit between the outer wall 22 of the inner crown 20 and the inner wall 31 of the outer crown 30 of the restoration tooth “T”.
The conventional method described above has another limitation. As illustrated in FIGS. 5–7, there are two natural teeth 10a and 10b which are to be restored by a restoration tooth “T′” having two outer crowns 30′. The restoration tooth “T′” is joined with the two natural teeth 10a and 10b such that the two outer crowns 30′ are respectively fitted over the abutments 20′ of the two natural teeth 10a and 10b under the circumstances that the center lines of the two abutments 20′ are parallel to each other. In the event that the two abutments 20′ are not made correctly by a dentist, it is very likely that the center lines of the two abutments 20′ are not parallel to each other, as illustrated in FIG. 7. As a result, the two outer crowns 30′ of the restoration tooth “T′” are not properly fitted over the two abutments 20′.